Typewriting machine



Sept. 10, 1929. A. G. REIMERS TYPEWRITING MACHINE Filed March 30, 1929Patented Sept. 10, 1929.

UNITED STATES ARTHUR G. REIMERS, OF MILWAUKEE,

PATENT OFFICE.

WISCONSIN, .ASSIGNOR TO UNDERWOOD ELLIOTT FISHER COMPANY, OF NEW YORK,N. Y., A CORPORATION OF DELAWARE;

TYPEWRITING MACHINE.

Application filed March 30, 1929. Serial No."351,215.

The present invention relates generally to ribbon-vibrating devices forfront-strike typewriting machines, and more particularly to avoidingfaulty operation of such devices at high speed. s

In a front-strike typewriting machine, shortly before the type-barreaches the platen, the former engages a universal bar, which causes amechanism to vibrate the ribio bon upwardly in front of the printingpoint. It is desirable in typewriter-construction to reduce the powerrequired for vibrating the ribbon, since this power is created by thepressure of the operators fingers on the typewriter-keys, and everyreduction in the power required for vibrating the ribbon makes for alighter touch for the typewriting machine. Furthermore, in rapidlyoperating a typewriting machine, such as the Underwood, which is widelyused for high-speed work, the operators fingers, when depressing thekeys, frequently do not complete the stroke or follow through, and theimpact of the type against the platen is then dependent upon themomentum of the type-bar. It

is important that the ribbon-vibrating mechanism operate properly,otherwise anyretarding action, such as may be caused by gumming andundue friction, will act through the unyielding connection of thevibrating mechanism and the type-bar, to bring a braking action, so tospeak, on the movement of the type-bar, and a weaker impact of the typeagainst the platen will result therefrom.

Free movement of the ribbon-vibrator in an Underwood typewriting machineis sometimes found to be retarded by detritus from erasures lodgingbetween the ribbon-vibrator and the rear face of a fixed segment-memberagainst which the vibrator slides up and down. It has been the practiceto oil the vibrator, yet it is found to have occasional faulty action athigh speeds. In some instances the Vibrator stays in its top position,and has other erratic tendencies.

A feature of the present invention resides in the provision of aribbon-vibrator having means to prevent the accumulation of suchfriction-creating matter between it and the fixed segment, therebyovercoming these faults. In carrying out this feature, dis charge holesare made in the body of the ribbon-vibrator and spaced along itslongitudinal axis. To make these holes more eflicient in dischargingsuch matter, it is a further feature of the invention to have the'holesflared rearwardly, that is, away from the segment. These holes furtherconduce to efficiency of lubrication, without incurring the formertrouble of adhesion between the vi brator and the segment, due to theoil.

Other features and advantages will hereinafter appear.

In'the accompanying drawings,

Figure 1 is a fragmentary front view'of an Underwood typewriting machinehaving the present invention applied thereto.

Figure 2 is a fragmentary cross-sectional view, from front to rear,through the structure shown in Figure 1. i

Figure 3 is a rear perspective view of the structure shown in Figure 1.

In an Underwood standard typewriting machine, to which the presentinvention may be advantageously applied, each type-bar 10 carries types11, either of which, upon 'de-' pression of an associated key (notshown), may be swung against a platen 12, whichis mounted on a shaft 13,journaled in a usual platen-frame (not shown).

An ink-ribbon 14, carried on two usual ribbon-spools 15, is movedupwardly in front of the printing point just before each type strikesthe sheet l/V on the platen. The ribbon 14, in front of the printingpoint, is sup ported on a ribbon-guide 16. The upper end portion of theguide is formed with forks'17, one fork on each side of the printingpoint.

To secure against lateral displacement, each fork 17 has a guide-finger18, which engages the side of a usual vertically-disposed type-guide 20,which is mounted on the usual segment 21, rigidly fastened to the frame22 of the machine. 1 Q

The ribbon-guide includes a body 23, whose lower portion is arranged intwo forksQ/i, whose lower end portions are curled around a pin 25, whichextends across a lengthwise slot 26 in the body 28. i 1

roe

The usual ribb0n-vibrator lever 27 is pivoted upon a pin 28, and may berocked by a universal-bar device (not shown), which may selectivelyengage either of two fulcrum-pins 29,30 in a manner substantially as setforth in Patent No. 926,050, granted to F. A. Cook, June 22, 1909.

It can be seen from inspection of Figures 2* and 3 that the ribbon-guide16 slides up and down between the usual fixed guide-plate 31 and a faceof the fixed segment 21 almost vertically under the printing point. Thisarrangement makes it possible for small bits of rubber, paper, or othererasing detritus to lodge between the ribbon-guide and the segment. Thisdetritus heretofore has not always been quickly discharged or removed,and. consequently sometimes caused a retarding action and faultiness inthe movement of the ribbon-guide mentioned above.

It is a feature of the present invention to arrange for immediatelyremoving bits of rubber and other erasure detritus which may lodgebetween the ribbon-guide 16 and the segment 21, byproviding, in the'bodyof the ribbon-guide, a plurality of openings 32, which are spaced'alongthe longitudinal axis of the body 23 of the ribbon-guide, and twosmaller holes 33-, one at each side of the axis, adjacent the lower endof a usual bifurcating slot 3.4, whose lower end terminatessubstantially even with the top of the segment 21. Itcan be seenbyinspection of Figures 1 and 3 that the apertures. 33. co-operate withthe slot 34 to help prevent detritus, etc.,. from passing downwardlybetween the body 23 and the segment 21. To further increase theefliciency of the holes 32, 33, in discharging detritus quickly, theyare flare-d rearwardly,

as illustrated in Figure 2, and it can be readily seen that a bit. ofdetritus finding its way into one of the holes will immediately rollawayfrom the face of the segment 21.

The holes. 32 also provide another advantage. Heretofore, when theribbon-guide 16 was. given excess of unsuitable lubrication, theresometimes resulted a kind of adhesion or mild suction between the body23 of the ribbon-guide and the segment 21, which operated to slightlyhinder the free movement of the ribbon-guide. The holes 32 will greatlythe same time, reduce the weight of the ribhon-guide 16a relativelylarge amount, which is desirable. 1

Having thus described my invention, I cla m:

1. In a front-strike typewriting machine having a platen and a fixedmember with an upright surface below the printing point of said platen,a vibrating ribbon-guide sliding against said surface, said guide havinga plurality of apertures through it, extending from its side adjacentsaid member through the opposite side, said apertures arranged forremoving detritus lodging between said ribbonguide and said surface.

2. In a typewriting machine having 2. revoluble platen, the combinationwith a fixed member of said machine disposed below the printing point ofsaid platen and having an upright surface, of a ribbon-guide moving upand down against said surface, said guide having a plurality ofapertures through it arranged for discharging friction-causing detritusaccumulating between said ribbonguide and said member.

3. In a frontstrike typewriting machine having a platen and a fixedmember with an upright surface below the printing point of said platen,a ribbon-guide moving up and down against said surface, said guidehaving a plurality of holes through it, extending from its side adjacentsaid member through the opposite side, said holes arranged fordischarging detritus lodging between said ribbon-guide and said surface,and said holes being flared away from said surface for quicklydischarging detritus disposed therein.

In a front-strike typewriting machine having a platen and a fixed memberwith an upright surface below the printing point of said platen, aribbon-guide vibrating up and down against said surface and having aforked upper portion formed by a bifurcating slot extending downwardlysubstantially to the top. of said member, said ribbon-guide having twoapertures through it, one spaced on each side of said slot adjacent thelower end thereof, and a plurality of additional lower apertures spacedalong the length of said ribbon-guide, said apertures extending from theface of said ribbon-guide adjacent said member through the opposite facefor the purpose specified.

ARTHUR G. REIMERS.

